Lawyers for Hobby Lobby this week urged the Supreme Court to let companies opt out of certain health insurance rules for religious reasons, and they have a good chance of success. If employers are allowed to refuse to provide coverage that pays for certain types of contraception, it will be a big victory for religious conservatives. Or will it?

After all, they have found before that getting your way does not always mean advancing your cause. Sometimes winning is a recipe for defeat.

That was the surprising case with same-sex marriage. Not long ago, public opinion was strongly opposed to it. Going into Election Day 2012, same-sex marriage had been put before the voters in statewide referendums 32 times, and 32 times it had lost.

Besides upholding "traditional marriage," these measures helped elect Republicans. Former Republican National Committee Chairman Ken Mehlman said that in 2004 and 2006, White House strategist Karl Rove worked to get same-sex marriage on the ballot to spur social conservatives to get to the polls.

But in 2012, the balance shifted. Gay marriage was approved by voters in all four states considering the issue. Since then, opponents have lost a Supreme Court decision, and 17 states now permit gays and lesbians to marry. A Gallup poll last year found that 54 percent of Americans support the idea -- up from 27 percent in 1996.

Much of the opposition comes from Christians who see it as an affront to God's law and an assault on the foundation of society. When a ban appeared on the California ballot in 2008, the Catholic Church, evangelical groups and the Mormon Church joined in campaigning for it. A Catholic bishop explained the alliance as one of believers who understand same-sex marriage to be "an attack of the Evil One."

But most people who support same-sex marriage don't think they are under the influence of Satan. Statements like that had two effects: 1) discrediting opponents by making it appear they had no basis except their interpretation of the word of God, and 2) driving supporters of same-sex marriage away from churches and faith itself.

The rise of support for gay matrimony has mirrored the decline of conservative Christianity. In his book "The Great Evangelical Recession," evangelical pastor John S. Dickerson concludes that the number of people attending his type of church is falling. And he acknowledges one big reason: "The most common belief about Bible-believing Christians today is that we are homophobic, anti-gay bigots."

That's one reason so many people have decided religion is not for them. The Pew Research Center reported in 2012 that the percentage of American adults with no religious affiliation has reached nearly 20 percent, with nearly a third of those calling themselves atheists or agnostics. Among those under 30, the numbers are even higher.

Those statistics are bad news for Republicans and conservative causes in general, since 63 percent of the "nones" lean Democratic, with only 26 percent preferring the GOP. Those on the religious right find that their vocal rejection of same-sex marriage, once an asset, has become an albatross.

If religious opposition to same-sex marriage isn't enough to turn off voters, religious opposition to contraception should be. The Hobby Lobby case promises to spread the news that many conservative Christians and Republicans take a dim view of birth control.

Mike Huckabee, who may run for president in 2016, recently said that Democrats favor mandated contraceptive coverage to make women believe "they cannot control their libido or their reproductive system without the help of the government." Rick Santorum, who ran in 2012, said then that contraception is "not OK, because it's a license to do things in the sexual realm that is counter to how things are supposed to be." The Catholic Church opposes all contraception.

If Hobby Lobby wins in the Supreme Court, conservatives will stand with business owners who regard contraception as forbidden by their faith and exclude it from the health insurance they provide employees. As that policy is embraced by other religious capitalists, it will convey to everyone that if you use birth control, you're at odds with Christianity and the Republican Party.

The Guttmacher Institute reports that more than 99 percent of women aged 15-44 who have ever had sex have used at least one type of contraception. Conservatives probably can't antagonize this entire group, but you have to give them credit for trying.